Pipe-covering and fabric from which pipe-coverings are made



UNITED` STATES PATENT OFFICE.v

ABRAM K. BURGSTRESSER, OF NORRISTOWN, PENNSYLVANIA, ASSIGNOR. T

NORRISTOWN MAG-NESIA AND ASBESTOS CO., OF NORRISTOWN, PENNSYL- VANIA, A CORPORATION OF PENNSYLVANIA.

Specification of Letters Patent. I

Patented Aug. 9, 1921.

Application led September 25, 1920. Serial No. 412,788.

To all whom t may concern Be it known that I, ABRAM K. BURG- s'rREssER, a citizen of the United States, residing at Norristown, in the county of Montgomery and State of Pennsylvania, have invented certain new and useful Improvements in Pipe-Coverings and Fabric ever desired and replaced without loss of fabric and one which keeps its good qualities indefinitely. In the drawing herewith I have shown in Figure 1, in diagram, the three vats from which my three ply fabric is procured;

Fig. 2 shows on a greatly enlarged scale a section through my fabric;

Fig. 3 shows the appearance of one side of the fabric;

Fig. 4 another, and

Fig. 5 is a section of a steam pipe showing alsomy pipe covering split and in cross section and the means for holding it in place.

In the drawing 1 represents my complete fabric. This fabric is composed preferably of three layers 2, 3 and 4. These layers are brought together upon wire 5 of a paper machine forming three cylinders, 6, 7 and 8; some of these cylinders being typical of any proper source of material which is supplied to the tanks 9, 10 and 1l. The material which I supply to my tanks 9 and 11 and which makes the inner and outer layers of my fabric is referably asbestos pulp, mainl or entire y. The intermediate or core ayer 3, which comes from the tank or tanks 10, is made of a granular porous material held together by enough asbestos fibers to give it suiiicient coherence to be taken from the cylinder to the wire.

Pulp then in the tank 10 is composed of the granular porous matter which may be and preferably is diatomaceous earth or kieselguhr wlth a certain proportionof asbestos. Instead of the diatomaceous earth other things like magnesia or other porous heat reslstant materials may be employed. The object is to provide in the exterior layers the necessary strength-giving qualities and 1n the intermediate layers 3, which I preferably make somewhat thicker than the outer layers, as great ability as possible to resist the passage of heat.

In taking the three surfaces which constitute my fabric from the machines I preferably roughening the opposite outer faces of the finished fabric. This roughening is preferably more marked on one side of the fabric than on the other, though it is seen on both sides, the under sideY having also the marks of the wire. I have illustrated the difference in these two sides in Figs. 3 and 4 wherein Fig. 3 represents the less strongly marked and F 1g. 4 the more strongly marked faces of the fabric.. My fabric yafter completion is wound in the usual way upon mandrels so as to make the pipe covering as thick as desired and the different layers are united by a heat resistant adhesive, preferably a silicate such as sodium silicate in solution. The adhesive may be applied by any suitable apparatus, but such apparatus is not a part of my present invention and it will be unnecessary to describe same herein. This adhesive is put on lightly and the winding or coiling upon the mandrel is also done rather lightly so that the whole thickness of the pipe covering is permeated with layers or zones of either cells or entrapped air. The roughenin effect produces certain ridges in the fabrlc on which the adhesive takes and the fabric being coiled under rather light pressure the s aces between the ridges become more or ess the cells of which I have spoken above.

The product thus made is provided with the usual muslin covering 13, is split as shown at 14 to be easily put around the pipe and at certain given distances along its length the whole is united by the usual brass straps or bands 15.

It will be seen that I have thus made a fabric which is composed of alternating layers of porous heat resistant material, fabric heat resistant material, air cells and fibrous heat resistant materials. I have found this fabric very eiiicient in conserving heat and economical in use.

I wish to be understood in the above description as reserving the right to all substantial equivalents of the material herein indicated.

Having thus described my invention,what.

principally of asbestos and an intermediate layer composed principally of heat insulating non-fibrous material.

3. In a heat insulating fabric in combination,'outer layers of strong iireproof fibrous material 'and an intermediate layer composed principally of granular, porous fireproof material.

4Q In a heat insulating fabric in combination, outer layers of asbestos paper and an intermediate layer of infusorial earth and asbestos, the outer faces being roughened.

5. In a heat insulating fabric in combination, outer layersof asbestos paper and an intermediate layer of infusorial earth and asbestos, the outer faces being roughened, and the whole wound into a tube with layers of sodium silicate to hold the other layers together.

6. A covering consisting of alternating layers of asbestos three-ply fabric roughened on the outer faces and silicate adhesive uniting the layers, the adhesive arranged to take upon only the prominent parts of the roughened surfaces whereby layers of air cells are distributedin alternationwith the layers of fabric throughout the pipe covering.

7. In a pipe covering in combination,

spiral layers of a three-ply fabric made of two layers of roughened asbestos paper and an intermediate layer of infusorial earth and asbestos, and layers of silicate adhesive, the adhesive taking on prominent parts of the surface of the three-ply fabric whereby layers or zones of air cells are left between the layers or zones of three-ply fabric.

In testimony whereof aiX my si nature.

ABRA'M K. BURGSTRE SER. 

